O'Connor was part of a team that made discoveries of extraordinary Enantiornithes remains preserved in Burmese amber. These deposits dated to 99 million
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Luis M.; GAO, Chunling; CHENG, Xiaodong (2010-03-22). "New Species of Enantiornithes (Aves: Ornithothoraces) from the Qiaotou Formation in Northern Hebei
produced dinosaur eggs, along with the indeterminate remains of avialans, enantiornithes, and possible indeterminate abelisaurids. Earth sciences portal Paleontology
Mongolian Late Cretaceous, and a General Appraisal of the Infraclass Enantiornithes". Palaeontological Institute of the Russian Academy of Sciences, Moskou
and systematics of the Cretaceous Euenantiornithes (Ornithothoraces: Enantiornithes)". Mesozoic Birds, above the heads of Dinosaurs. Berkeley: University
M. A.; Clark, J. (2001). "A New Skull of Gobipteryx minuta (Aves: Enantiornithes) from the Cretaceous of the Gobi Desert" (PDF). American Museum Novitates
O. Calvo (1994). "Neuquenornis volans, a New Late Cretaceous Bird (Enantiornithes: Avisauridae) from Patagonia, Argentina" (PDF). Journal of Vertebrate
M. A.; Clark, J. (2001). "A New Skull of Gobipteryx minuta (Aves: Enantiornithes) from the Cretaceous of the Gobi Desert" (PDF). American Museum Novitates
(2020-12-01). "New information on the plumage of Protopteryx (Aves: Enantiornithes) from a new specimen". Cretaceous Research. 116: 104577. Bibcode:2020CrRes